Application of ultrasonic waves to assess grain structure in cast stainless steel

Conference · Mon Apr 01 04:00:00 EST 1985

OSTI ID:5235803

Kupperman, D S; Reimann, K J; Abrego-Lopez, J

Although the ASME code requires the inspection of cast stainless steel (CSS) piping in nuclear reactors, it has not been possible to demonstrate unambiguously that current inspection techniques are adequate. Ultrasonic inspection is difficult because the microstructure of CSS can vary considerably, from elastically isotropic with equiaxed, relatively small grains to elastically anisotropic with a columnar grain structure to a combination of the two. For the near term, improvements that may increase the reliability of ultrasonic inspection include (a) the development of methods to establish the microstructure of the material (to help optimize the inspection technique), (b) the identification of calibration standards that are more representative of the material to be inspected and (c) the use of cracked CSS samples for training purposes. In this paper, the results of experiments to characterize the microstructure of CSS by use of ultrasonic waves will be discussed. Shear waves may be more effective for isotropic material, whereas longitudinal waves may be better for the anisotropic case because of beam-focusing effects. Sound velocity and beam skewing can be measured accurately enough to characterize CSS even in thick-walled reactor components. 5 refs., 6 figs., 2 tabs.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5235803
• Report Number(s): CONF-851151-1; ON: TI85011475
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360103 -- Metals & Alloys-- Mechanical Properties
ACOUSTIC TESTING
ALLOYS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-NICKEL STEELS
CORROSION RESISTANT ALLOYS
CRACKS
CRYSTAL STRUCTURE
DATA
EXPERIMENTAL DATA
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IN-SERVICE INSPECTION
INFORMATION
INSPECTION
IRON ALLOYS
IRON BASE ALLOYS
MAINTENANCE
MATERIALS
MATERIALS TESTING
MICROSTRUCTURE
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NONDESTRUCTIVE TESTING
NUMERICAL DATA
PIPES
REACTOR MAINTENANCE
SIGNAL-TO-NOISE RATIO
SOUND WAVES
STAINLESS STEEL-304
STAINLESS STEEL-304L
STAINLESS STEEL-316
STAINLESS STEELS
STEELS
TESTING
ULTRASONIC TESTING
ULTRASONIC WAVES
VELOCITY